This invention relates to a pilot stage valve that can be used for controlling servo valves and the like, and more particularly to the magnetic operator and receiving sections for the pilot stage valve.
Typical prior art pilot stage valves include a magnetic operator having north and south magnets, pole pieces and a winding wound around an armature. The winding is energized from an external input signal to magnetize the armature either north or south. Once magnetized, the armature will move away from one magnet to the other depending upon its polarity to control the distance between the armature and one of two input ports. This distance controls the pressure within the input ports which in turn can be used to control the position of a servo valve stage or spool. A feedback mechanism is sometimes connected between the spool of the servo valve and the armature of the magnetic operator section. Such an arrangement is shown in U.S. Pat. No. 3,749,129 issued July 31, 1973.
These prior art valves are bulky and costly to assemble. The pilot stage valve according to the present invention is smaller in size than typical prior art pilot stage valves and is more economical to assemble.